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From:   khalasa@piap.pl (Krzysztof =?utf-8?Q?Ha=C5=82asa?=)
To:     Johannes Berg <johannes@sipsolutions.net>
Cc:     "David S. Miller" <davem@davemloft.net>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH v2] 802.11n IBSS: wlan0 stops receiving packets due to aggregation after sender reboot
In-Reply-To: <m34l02mh71.fsf@t19.piap.pl>
References: <m34l02mh71.fsf@t19.piap.pl>
Date:   Fri, 25 Oct 2019 12:21:25 +0200
Message-ID: <m37e4tjfbu.fsf@t19.piap.pl>
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Fix a bug where the mac80211 RX aggregation code sets a new aggregation
"session" at the remote station's request, but the head_seq_num
(the sequence number the receiver expects to receive) isn't reset.

Spotted on a pair of AR9580 in IBSS mode.

Signed-off-by: Krzysztof Halasa <khalasa@piap.pl>

diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index 4d1c335e06e5..67733bd61297 100644
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -354,10 +354,13 @@ void ___ieee80211_start_rx_ba_session(struct sta_info=
 *sta,
 			 */
 			rcu_read_lock();
 			tid_rx =3D rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
-			if (tid_rx && tid_rx->timeout =3D=3D timeout)
+			if (tid_rx && tid_rx->timeout =3D=3D timeout) {
+				tid_rx->ssn =3D start_seq_num;
+				tid_rx->head_seq_num =3D start_seq_num;
 				status =3D WLAN_STATUS_SUCCESS;
-			else
+			} else {
 				status =3D WLAN_STATUS_REQUEST_DECLINED;
+			}
 			rcu_read_unlock();
 			goto end;
 		}

--=20
Krzysztof Ha=C5=82asa

=C5=81UKASIEWICZ Research Network
Industrial Research Institute for Automation and Measurements PIAP
Al. Jerozolimskie 202, 02-486 Warsaw, Poland